git.sesse.net Git - nageru/blob - mixer.cpp

   1 #undef Success
   2
   3 #include "mixer.h"
   4
   5 #include <assert.h>
   6 #include <endian.h>
   7 #include <epoxy/egl.h>
   8 #include <movit/effect_chain.h>
   9 #include <movit/effect_util.h>
  10 #include <movit/flat_input.h>
  11 #include <movit/image_format.h>
  12 #include <movit/init.h>
  13 #include <movit/resource_pool.h>
  14 #include <movit/util.h>
  15 #include <stdint.h>
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include <sys/resource.h>
  19 #include <sys/time.h>
  20 #include <time.h>
  21 #include <algorithm>
  22 #include <chrono>
  23 #include <cmath>
  24 #include <condition_variable>
  25 #include <cstddef>
  26 #include <memory>
  27 #include <mutex>
  28 #include <string>
  29 #include <thread>
  30 #include <utility>
  31 #include <vector>
  32
  33 #include "bmusb/bmusb.h"
  34 #include "bmusb/fake_capture.h"
  35 #include "context.h"
  36 #include "db.h"
  37 #include "decklink_capture.h"
  38 #include "defs.h"
  39 #include "disk_space_estimator.h"
  40 #include "flags.h"
  41 #include "pbo_frame_allocator.h"
  42 #include "ref_counted_gl_sync.h"
  43 #include "timebase.h"
  44 #include "video_encoder.h"
  45
  46 class QOpenGLContext;
  47
  48 using namespace movit;
  49 using namespace std;
  50 using namespace std::chrono;
  51 using namespace std::placeholders;
  52 using namespace bmusb;
  53
  54 Mixer *global_mixer = nullptr;
  55 bool uses_mlock = false;
  56
  57 namespace {
  58
  59 void insert_new_frame(RefCountedFrame frame, unsigned field_num, bool interlaced, unsigned card_index, InputState *input_state)
  60 {
  61         if (interlaced) {
  62                 for (unsigned frame_num = FRAME_HISTORY_LENGTH; frame_num --> 1; ) {  // :-)
  63                         input_state->buffered_frames[card_index][frame_num] =
  64                                 input_state->buffered_frames[card_index][frame_num - 1];
  65                 }
  66                 input_state->buffered_frames[card_index][0] = { frame, field_num };
  67         } else {
  68                 for (unsigned frame_num = 0; frame_num < FRAME_HISTORY_LENGTH; ++frame_num) {
  69                         input_state->buffered_frames[card_index][frame_num] = { frame, field_num };
  70                 }
  71         }
  72 }
  73
  74 }  // namespace
  75
  76 void QueueLengthPolicy::update_policy(int queue_length)
  77 {
  78         if (queue_length < 0) {  // Starvation.
  79                 if (been_at_safe_point_since_last_starvation && safe_queue_length < 5) {
  80                         ++safe_queue_length;
  81                         fprintf(stderr, "Card %u: Starvation, increasing safe limit to %u frames\n",
  82                                 card_index, safe_queue_length);
  83                 }
  84                 frames_with_at_least_one = 0;
  85                 been_at_safe_point_since_last_starvation = false;
  86                 return;
  87         }
  88         if (queue_length > 0) {
  89                 if (queue_length >= int(safe_queue_length)) {
  90                         been_at_safe_point_since_last_starvation = true;
  91                 }
  92                 if (++frames_with_at_least_one >= 1000 && safe_queue_length > 0) {
  93                         --safe_queue_length;
  94                         fprintf(stderr, "Card %u: Spare frames for more than 1000 frames, reducing safe limit to %u frames\n",
  95                                 card_index, safe_queue_length);
  96                         frames_with_at_least_one = 0;
  97                 }
  98         } else {
  99                 frames_with_at_least_one = 0;
 100         }
 101 }
 102
 103 Mixer::Mixer(const QSurfaceFormat &format, unsigned num_cards)
 104         : httpd(),
 105           num_cards(num_cards),
 106           mixer_surface(create_surface(format)),
 107           h264_encoder_surface(create_surface(format)),
 108           audio_mixer(num_cards),
 109           correlation(OUTPUT_FREQUENCY)
 110 {
 111         CHECK(init_movit(MOVIT_SHADER_DIR, MOVIT_DEBUG_OFF));
 112         check_error();
 113
 114         // Since we allow non-bouncing 4:2:2 YCbCrInputs, effective subpixel precision
 115         // will be halved when sampling them, and we need to compensate here.
 116         movit_texel_subpixel_precision /= 2.0;
 117
 118         resource_pool.reset(new ResourcePool);
 119         theme.reset(new Theme(global_flags.theme_filename, global_flags.theme_dirs, resource_pool.get(), num_cards));
 120         for (unsigned i = 0; i < NUM_OUTPUTS; ++i) {
 121                 output_channel[i].parent = this;
 122                 output_channel[i].channel = i;
 123         }
 124
 125         ImageFormat inout_format;
 126         inout_format.color_space = COLORSPACE_sRGB;
 127         inout_format.gamma_curve = GAMMA_sRGB;
 128
 129         // Display chain; shows the live output produced by the main chain (its RGBA version).
 130         display_chain.reset(new EffectChain(WIDTH, HEIGHT, resource_pool.get()));
 131         check_error();
 132         display_input = new FlatInput(inout_format, FORMAT_RGB, GL_UNSIGNED_BYTE, WIDTH, HEIGHT);  // FIXME: GL_UNSIGNED_BYTE is really wrong.
 133         display_chain->add_input(display_input);
 134         display_chain->add_output(inout_format, OUTPUT_ALPHA_FORMAT_POSTMULTIPLIED);
 135         display_chain->set_dither_bits(0);  // Don't bother.
 136         display_chain->finalize();
 137
 138         video_encoder.reset(new VideoEncoder(resource_pool.get(), h264_encoder_surface, global_flags.va_display, WIDTH, HEIGHT, &httpd, global_disk_space_estimator));
 139
 140         // Start listening for clients only once VideoEncoder has written its header, if any.
 141         httpd.start(9095);
 142
 143         // First try initializing the then PCI devices, then USB, then
 144         // fill up with fake cards until we have the desired number of cards.
 145         unsigned num_pci_devices = 0;
 146         unsigned card_index = 0;
 147
 148         {
 149                 IDeckLinkIterator *decklink_iterator = CreateDeckLinkIteratorInstance();
 150                 if (decklink_iterator != nullptr) {
 151                         for ( ; card_index < num_cards; ++card_index) {
 152                                 IDeckLink *decklink;
 153                                 if (decklink_iterator->Next(&decklink) != S_OK) {
 154                                         break;
 155                                 }
 156
 157                                 configure_card(card_index, new DeckLinkCapture(decklink, card_index), /*is_fake_capture=*/false);
 158                                 ++num_pci_devices;
 159                         }
 160                         decklink_iterator->Release();
 161                         fprintf(stderr, "Found %u DeckLink PCI card(s).\n", num_pci_devices);
 162                 } else {
 163                         fprintf(stderr, "DeckLink drivers not found. Probing for USB cards only.\n");
 164                 }
 165         }
 166         unsigned num_usb_devices = BMUSBCapture::num_cards();
 167         for (unsigned usb_card_index = 0; usb_card_index < num_usb_devices && card_index < num_cards; ++usb_card_index, ++card_index) {
 168                 BMUSBCapture *capture = new BMUSBCapture(usb_card_index);
 169                 capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, card_index));
 170                 configure_card(card_index, capture, /*is_fake_capture=*/false);
 171         }
 172         fprintf(stderr, "Found %u USB card(s).\n", num_usb_devices);
 173
 174         unsigned num_fake_cards = 0;
 175         for ( ; card_index < num_cards; ++card_index, ++num_fake_cards) {
 176                 FakeCapture *capture = new FakeCapture(WIDTH, HEIGHT, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 177                 configure_card(card_index, capture, /*is_fake_capture=*/true);
 178         }
 179
 180         if (num_fake_cards > 0) {
 181                 fprintf(stderr, "Initialized %u fake cards.\n", num_fake_cards);
 182         }
 183
 184         BMUSBCapture::set_card_connected_callback(bind(&Mixer::bm_hotplug_add, this, _1));
 185         BMUSBCapture::start_bm_thread();
 186
 187         for (card_index = 0; card_index < num_cards; ++card_index) {
 188                 cards[card_index].queue_length_policy.reset(card_index);
 189                 cards[card_index].capture->start_bm_capture();
 190         }
 191
 192         // Set up stuff for NV12 conversion.
 193
 194         // Cb/Cr shader.
 195         string cbcr_vert_shader =
 196                 "#version 130 \n"
 197                 " \n"
 198                 "in vec2 position; \n"
 199                 "in vec2 texcoord; \n"
 200                 "out vec2 tc0; \n"
 201                 "uniform vec2 foo_chroma_offset_0; \n"
 202                 " \n"
 203                 "void main() \n"
 204                 "{ \n"
 205                 "    // The result of glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0) is: \n"
 206                 "    // \n"
 207                 "    //   2.000  0.000  0.000 -1.000 \n"
 208                 "    //   0.000  2.000  0.000 -1.000 \n"
 209                 "    //   0.000  0.000 -2.000 -1.000 \n"
 210                 "    //   0.000  0.000  0.000  1.000 \n"
 211                 "    gl_Position = vec4(2.0 * position.x - 1.0, 2.0 * position.y - 1.0, -1.0, 1.0); \n"
 212                 "    vec2 flipped_tc = texcoord; \n"
 213                 "    tc0 = flipped_tc + foo_chroma_offset_0; \n"
 214                 "} \n";
 215         string cbcr_frag_shader =
 216                 "#version 130 \n"
 217                 "in vec2 tc0; \n"
 218                 "uniform sampler2D cbcr_tex; \n"
 219                 "out vec4 FragColor; \n"
 220                 "void main() { \n"
 221                 "    FragColor = texture(cbcr_tex, tc0); \n"
 222                 "} \n";
 223         vector<string> frag_shader_outputs;
 224         cbcr_program_num = resource_pool->compile_glsl_program(cbcr_vert_shader, cbcr_frag_shader, frag_shader_outputs);
 225
 226         float vertices[] = {
 227                 0.0f, 2.0f,
 228                 0.0f, 0.0f,
 229                 2.0f, 0.0f
 230         };
 231         cbcr_vbo = generate_vbo(2, GL_FLOAT, sizeof(vertices), vertices);
 232         cbcr_position_attribute_index = glGetAttribLocation(cbcr_program_num, "position");
 233         cbcr_texcoord_attribute_index = glGetAttribLocation(cbcr_program_num, "texcoord");
 234
 235         r128.init(2, OUTPUT_FREQUENCY);
 236         r128.integr_start();
 237
 238         // hlen=16 is pretty low quality, but we use quite a bit of CPU otherwise,
 239         // and there's a limit to how important the peak meter is.
 240         peak_resampler.setup(OUTPUT_FREQUENCY, OUTPUT_FREQUENCY * 4, /*num_channels=*/2, /*hlen=*/16, /*frel=*/1.0);
 241
 242         if (global_flags.enable_alsa_output) {
 243                 alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
 244         }
 245 }
 246
 247 Mixer::~Mixer()
 248 {
 249         resource_pool->release_glsl_program(cbcr_program_num);
 250         glDeleteBuffers(1, &cbcr_vbo);
 251         BMUSBCapture::stop_bm_thread();
 252
 253         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 254                 {
 255                         unique_lock<mutex> lock(bmusb_mutex);
 256                         cards[card_index].should_quit = true;  // Unblock thread.
 257                         cards[card_index].new_frames_changed.notify_all();
 258                 }
 259                 cards[card_index].capture->stop_dequeue_thread();
 260         }
 261
 262         video_encoder.reset(nullptr);
 263 }
 264
 265 void Mixer::configure_card(unsigned card_index, CaptureInterface *capture, bool is_fake_capture)
 266 {
 267         printf("Configuring card %d...\n", card_index);
 268
 269         CaptureCard *card = &cards[card_index];
 270         if (card->capture != nullptr) {
 271                 card->capture->stop_dequeue_thread();
 272                 delete card->capture;
 273         }
 274         card->capture = capture;
 275         card->is_fake_capture = is_fake_capture;
 276         card->capture->set_frame_callback(bind(&Mixer::bm_frame, this, card_index, _1, _2, _3, _4, _5, _6, _7));
 277         if (card->frame_allocator == nullptr) {
 278                 card->frame_allocator.reset(new PBOFrameAllocator(8 << 20, WIDTH, HEIGHT));  // 8 MB.
 279         }
 280         card->capture->set_video_frame_allocator(card->frame_allocator.get());
 281         if (card->surface == nullptr) {
 282                 card->surface = create_surface_with_same_format(mixer_surface);
 283         }
 284         while (!card->new_frames.empty()) card->new_frames.pop();
 285         card->fractional_samples = 0;
 286         card->last_timecode = -1;
 287         card->capture->configure_card();
 288
 289         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 290         audio_mixer.reset_resampler(device);
 291         audio_mixer.set_name(device, card->capture->get_description());
 292 }
 293
 294
 295 namespace {
 296
 297 int unwrap_timecode(uint16_t current_wrapped, int last)
 298 {
 299         uint16_t last_wrapped = last & 0xffff;
 300         if (current_wrapped > last_wrapped) {
 301                 return (last & ~0xffff) | current_wrapped;
 302         } else {
 303                 return 0x10000 + ((last & ~0xffff) | current_wrapped);
 304         }
 305 }
 306
 307 float find_peak(const float *samples, size_t num_samples)
 308 {
 309         float m = fabs(samples[0]);
 310         for (size_t i = 1; i < num_samples; ++i) {
 311                 m = max(m, fabs(samples[i]));
 312         }
 313         return m;
 314 }
 315
 316 void deinterleave_samples(const vector<float> &in, vector<float> *out_l, vector<float> *out_r)
 317 {
 318         size_t num_samples = in.size() / 2;
 319         out_l->resize(num_samples);
 320         out_r->resize(num_samples);
 321
 322         const float *inptr = in.data();
 323         float *lptr = &(*out_l)[0];
 324         float *rptr = &(*out_r)[0];
 325         for (size_t i = 0; i < num_samples; ++i) {
 326                 *lptr++ = *inptr++;
 327                 *rptr++ = *inptr++;
 328         }
 329 }
 330
 331 }  // namespace
 332
 333 void Mixer::bm_frame(unsigned card_index, uint16_t timecode,
 334                      FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
 335                      FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)
 336 {
 337         DeviceSpec device{InputSourceType::CAPTURE_CARD, card_index};
 338         CaptureCard *card = &cards[card_index];
 339
 340         if (is_mode_scanning[card_index]) {
 341                 if (video_format.has_signal) {
 342                         // Found a stable signal, so stop scanning.
 343                         is_mode_scanning[card_index] = false;
 344                 } else {
 345                         static constexpr double switch_time_s = 0.5;  // Should be enough time for the signal to stabilize.
 346                         steady_clock::time_point now = steady_clock::now();
 347                         double sec_since_last_switch = duration<double>(steady_clock::now() - last_mode_scan_change[card_index]).count();
 348                         if (sec_since_last_switch > switch_time_s) {
 349                                 // It isn't this mode; try the next one.
 350                                 mode_scanlist_index[card_index]++;
 351                                 mode_scanlist_index[card_index] %= mode_scanlist[card_index].size();
 352                                 cards[card_index].capture->set_video_mode(mode_scanlist[card_index][mode_scanlist_index[card_index]]);
 353                                 last_mode_scan_change[card_index] = now;
 354                         }
 355                 }
 356         }
 357
 358         int64_t frame_length = int64_t(TIMEBASE) * video_format.frame_rate_den / video_format.frame_rate_nom;
 359         assert(frame_length > 0);
 360
 361         size_t num_samples = (audio_frame.len > audio_offset) ? (audio_frame.len - audio_offset) / audio_format.num_channels / (audio_format.bits_per_sample / 8) : 0;
 362         if (num_samples > OUTPUT_FREQUENCY / 10) {
 363                 printf("Card %d: Dropping frame with implausible audio length (len=%d, offset=%d) [timecode=0x%04x video_len=%d video_offset=%d video_format=%x)\n",
 364                         card_index, int(audio_frame.len), int(audio_offset),
 365                         timecode, int(video_frame.len), int(video_offset), video_format.id);
 366                 if (video_frame.owner) {
 367                         video_frame.owner->release_frame(video_frame);
 368                 }
 369                 if (audio_frame.owner) {
 370                         audio_frame.owner->release_frame(audio_frame);
 371                 }
 372                 return;
 373         }
 374
 375         int dropped_frames = 0;
 376         if (card->last_timecode != -1) {
 377                 dropped_frames = unwrap_timecode(timecode, card->last_timecode) - card->last_timecode - 1;
 378         }
 379
 380         // Number of samples per frame if we need to insert silence.
 381         // (Could be nonintegral, but resampling will save us then.)
 382         const int silence_samples = OUTPUT_FREQUENCY * video_format.frame_rate_den / video_format.frame_rate_nom;
 383
 384         if (dropped_frames > MAX_FPS * 2) {
 385                 fprintf(stderr, "Card %d lost more than two seconds (or time code jumping around; from 0x%04x to 0x%04x), resetting resampler\n",
 386                         card_index, card->last_timecode, timecode);
 387                 audio_mixer.reset_resampler(device);
 388                 dropped_frames = 0;
 389         } else if (dropped_frames > 0) {
 390                 // Insert silence as needed.
 391                 fprintf(stderr, "Card %d dropped %d frame(s) (before timecode 0x%04x), inserting silence.\n",
 392                         card_index, dropped_frames, timecode);
 393
 394                 bool success;
 395                 do {
 396                         success = audio_mixer.add_silence(device, silence_samples, dropped_frames, frame_length);
 397                 } while (!success);
 398         }
 399
 400         audio_mixer.add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, frame_length);
 401
 402         // Done with the audio, so release it.
 403         if (audio_frame.owner) {
 404                 audio_frame.owner->release_frame(audio_frame);
 405         }
 406
 407         card->last_timecode = timecode;
 408
 409         size_t expected_length = video_format.width * (video_format.height + video_format.extra_lines_top + video_format.extra_lines_bottom) * 2;
 410         if (video_frame.len - video_offset == 0 ||
 411             video_frame.len - video_offset != expected_length) {
 412                 if (video_frame.len != 0) {
 413                         printf("Card %d: Dropping video frame with wrong length (%ld; expected %ld)\n",
 414                                 card_index, video_frame.len - video_offset, expected_length);
 415                 }
 416                 if (video_frame.owner) {
 417                         video_frame.owner->release_frame(video_frame);
 418                 }
 419
 420                 // Still send on the information that we _had_ a frame, even though it's corrupted,
 421                 // so that pts can go up accordingly.
 422                 {
 423                         unique_lock<mutex> lock(bmusb_mutex);
 424                         CaptureCard::NewFrame new_frame;
 425                         new_frame.frame = RefCountedFrame(FrameAllocator::Frame());
 426                         new_frame.length = frame_length;
 427                         new_frame.interlaced = false;
 428                         new_frame.dropped_frames = dropped_frames;
 429                         card->new_frames.push(move(new_frame));
 430                         card->new_frames_changed.notify_all();
 431                 }
 432                 return;
 433         }
 434
 435         PBOFrameAllocator::Userdata *userdata = (PBOFrameAllocator::Userdata *)video_frame.userdata;
 436
 437         unsigned num_fields = video_format.interlaced ? 2 : 1;
 438         steady_clock::time_point frame_upload_start;
 439         if (video_format.interlaced) {
 440                 // Send the two fields along as separate frames; the other side will need to add
 441                 // a deinterlacer to actually get this right.
 442                 assert(video_format.height % 2 == 0);
 443                 video_format.height /= 2;
 444                 assert(frame_length % 2 == 0);
 445                 frame_length /= 2;
 446                 num_fields = 2;
 447                 frame_upload_start = steady_clock::now();
 448         }
 449         userdata->last_interlaced = video_format.interlaced;
 450         userdata->last_has_signal = video_format.has_signal;
 451         userdata->last_is_connected = video_format.is_connected;
 452         userdata->last_frame_rate_nom = video_format.frame_rate_nom;
 453         userdata->last_frame_rate_den = video_format.frame_rate_den;
 454         RefCountedFrame frame(video_frame);
 455
 456         // Upload the textures.
 457         size_t cbcr_width = video_format.width / 2;
 458         size_t cbcr_offset = video_offset / 2;
 459         size_t y_offset = video_frame.size / 2 + video_offset / 2;
 460
 461         for (unsigned field = 0; field < num_fields; ++field) {
 462                 // Put the actual texture upload in a lambda that is executed in the main thread.
 463                 // It is entirely possible to do this in the same thread (and it might even be
 464                 // faster, depending on the GPU and driver), but it appears to be trickling
 465                 // driver bugs very easily.
 466                 //
 467                 // Note that this means we must hold on to the actual frame data in <userdata>
 468                 // until the upload command is run, but we hold on to <frame> much longer than that
 469                 // (in fact, all the way until we no longer use the texture in rendering).
 470                 auto upload_func = [field, video_format, y_offset, cbcr_offset, cbcr_width, userdata]() {
 471                         unsigned field_start_line = (field == 1) ? video_format.second_field_start : video_format.extra_lines_top + field * (video_format.height + 22);
 472
 473                         if (userdata->tex_y[field] == 0 ||
 474                             userdata->tex_cbcr[field] == 0 ||
 475                             video_format.width != userdata->last_width[field] ||
 476                             video_format.height != userdata->last_height[field]) {
 477                                 // We changed resolution since last use of this texture, so we need to create
 478                                 // a new object. Note that this each card has its own PBOFrameAllocator,
 479                                 // we don't need to worry about these flip-flopping between resolutions.
 480                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 481                                 check_error();
 482                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RG8, cbcr_width, video_format.height, 0, GL_RG, GL_UNSIGNED_BYTE, nullptr);
 483                                 check_error();
 484                                 glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 485                                 check_error();
 486                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, video_format.width, video_format.height, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr);
 487                                 check_error();
 488                                 userdata->last_width[field] = video_format.width;
 489                                 userdata->last_height[field] = video_format.height;
 490                         }
 491
 492                         GLuint pbo = userdata->pbo;
 493                         check_error();
 494                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pbo);
 495                         check_error();
 496
 497                         size_t field_y_start = y_offset + video_format.width * field_start_line;
 498                         size_t field_cbcr_start = cbcr_offset + cbcr_width * field_start_line * sizeof(uint16_t);
 499
 500                         if (global_flags.flush_pbos) {
 501                                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, field_y_start, video_format.width * video_format.height);
 502                                 check_error();
 503                                 glFlushMappedBufferRange(GL_PIXEL_UNPACK_BUFFER, field_cbcr_start, cbcr_width * video_format.height * sizeof(uint16_t));
 504                                 check_error();
 505                         }
 506
 507                         glBindTexture(GL_TEXTURE_2D, userdata->tex_cbcr[field]);
 508                         check_error();
 509                         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, cbcr_width, video_format.height, GL_RG, GL_UNSIGNED_BYTE, BUFFER_OFFSET(field_cbcr_start));
 510                         check_error();
 511                         glBindTexture(GL_TEXTURE_2D, userdata->tex_y[field]);
 512                         check_error();
 513                         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, video_format.width, video_format.height, GL_RED, GL_UNSIGNED_BYTE, BUFFER_OFFSET(field_y_start));
 514                         check_error();
 515                         glBindTexture(GL_TEXTURE_2D, 0);
 516                         check_error();
 517                         glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
 518                         check_error();
 519                 };
 520
 521                 if (field == 1) {
 522                         // Don't upload the second field as fast as we can; wait until
 523                         // the field time has approximately passed. (Otherwise, we could
 524                         // get timing jitter against the other sources, and possibly also
 525                         // against the video display, although the latter is not as critical.)
 526                         // This requires our system clock to be reasonably close to the
 527                         // video clock, but that's not an unreasonable assumption.
 528                         steady_clock::time_point second_field_start = frame_upload_start +
 529                                 nanoseconds(frame_length * 1000000000 / TIMEBASE);
 530                         this_thread::sleep_until(second_field_start);
 531                 }
 532
 533                 {
 534                         unique_lock<mutex> lock(bmusb_mutex);
 535                         CaptureCard::NewFrame new_frame;
 536                         new_frame.frame = frame;
 537                         new_frame.length = frame_length;
 538                         new_frame.field = field;
 539                         new_frame.interlaced = video_format.interlaced;
 540                         new_frame.upload_func = upload_func;
 541                         new_frame.dropped_frames = dropped_frames;
 542                         card->new_frames.push(move(new_frame));
 543                         card->new_frames_changed.notify_all();
 544                 }
 545         }
 546 }
 547
 548 void Mixer::bm_hotplug_add(libusb_device *dev)
 549 {
 550         lock_guard<mutex> lock(hotplug_mutex);
 551         hotplugged_cards.push_back(dev);
 552 }
 553
 554 void Mixer::bm_hotplug_remove(unsigned card_index)
 555 {
 556         cards[card_index].new_frames_changed.notify_all();
 557 }
 558
 559 void Mixer::thread_func()
 560 {
 561         eglBindAPI(EGL_OPENGL_API);
 562         QOpenGLContext *context = create_context(mixer_surface);
 563         if (!make_current(context, mixer_surface)) {
 564                 printf("oops\n");
 565                 exit(1);
 566         }
 567
 568         steady_clock::time_point start, now;
 569         start = steady_clock::now();
 570
 571         int frame = 0;
 572         int stats_dropped_frames = 0;
 573
 574         while (!should_quit) {
 575                 CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
 576                 bool has_new_frame[MAX_VIDEO_CARDS] = { false };
 577                 int num_samples[MAX_VIDEO_CARDS] = { 0 };
 578
 579                 unsigned master_card_index = theme->map_signal(master_clock_channel);
 580                 assert(master_card_index < num_cards);
 581
 582                 get_one_frame_from_each_card(master_card_index, new_frames, has_new_frame, num_samples);
 583                 schedule_audio_resampling_tasks(new_frames[master_card_index].dropped_frames, num_samples[master_card_index], new_frames[master_card_index].length);
 584                 stats_dropped_frames += new_frames[master_card_index].dropped_frames;
 585                 send_audio_level_callback();
 586
 587                 handle_hotplugged_cards();
 588
 589                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 590                         if (card_index == master_card_index || !has_new_frame[card_index]) {
 591                                 continue;
 592                         }
 593                         if (new_frames[card_index].frame->len == 0) {
 594                                 ++new_frames[card_index].dropped_frames;
 595                         }
 596                         if (new_frames[card_index].dropped_frames > 0) {
 597                                 printf("Card %u dropped %d frames before this\n",
 598                                         card_index, int(new_frames[card_index].dropped_frames));
 599                         }
 600                 }
 601
 602                 // If the first card is reporting a corrupted or otherwise dropped frame,
 603                 // just increase the pts (skipping over this frame) and don't try to compute anything new.
 604                 if (new_frames[master_card_index].frame->len == 0) {
 605                         ++stats_dropped_frames;
 606                         pts_int += new_frames[master_card_index].length;
 607                         continue;
 608                 }
 609
 610                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 611                         if (!has_new_frame[card_index] || new_frames[card_index].frame->len == 0)
 612                                 continue;
 613
 614                         CaptureCard::NewFrame *new_frame = &new_frames[card_index];
 615                         assert(new_frame->frame != nullptr);
 616                         insert_new_frame(new_frame->frame, new_frame->field, new_frame->interlaced, card_index, &input_state);
 617                         check_error();
 618
 619                         // The new texture might need uploading before use.
 620                         if (new_frame->upload_func) {
 621                                 new_frame->upload_func();
 622                                 new_frame->upload_func = nullptr;
 623                         }
 624                 }
 625
 626                 int64_t frame_duration = new_frames[master_card_index].length;
 627                 render_one_frame(frame_duration);
 628                 ++frame;
 629                 pts_int += frame_duration;
 630
 631                 now = steady_clock::now();
 632                 double elapsed = duration<double>(now - start).count();
 633                 if (frame % 100 == 0) {
 634                         printf("%d frames (%d dropped) in %.3f seconds = %.1f fps (%.1f ms/frame)",
 635                                 frame, stats_dropped_frames, elapsed, frame / elapsed,
 636                                 1e3 * elapsed / frame);
 637                 //      chain->print_phase_timing();
 638
 639                         // Check our memory usage, to see if we are close to our mlockall()
 640                         // limit (if at all set).
 641                         rusage used;
 642                         if (getrusage(RUSAGE_SELF, &used) == -1) {
 643                                 perror("getrusage(RUSAGE_SELF)");
 644                                 assert(false);
 645                         }
 646
 647                         if (uses_mlock) {
 648                                 rlimit limit;
 649                                 if (getrlimit(RLIMIT_MEMLOCK, &limit) == -1) {
 650                                         perror("getrlimit(RLIMIT_MEMLOCK)");
 651                                         assert(false);
 652                                 }
 653
 654                                 printf(", using %ld / %ld MB lockable memory (%.1f%%)",
 655                                         long(used.ru_maxrss / 1024),
 656                                         long(limit.rlim_cur / 1048576),
 657                                         float(100.0 * (used.ru_maxrss * 1024.0) / limit.rlim_cur));
 658                         } else {
 659                                 printf(", using %ld MB memory (not locked)",
 660                                         long(used.ru_maxrss / 1024));
 661                         }
 662
 663                         printf("\n");
 664                 }
 665
 666
 667                 if (should_cut.exchange(false)) {  // Test and clear.
 668                         video_encoder->do_cut(frame);
 669                 }
 670
 671 #if 0
 672                 // Reset every 100 frames, so that local variations in frame times
 673                 // (especially for the first few frames, when the shaders are
 674                 // compiled etc.) don't make it hard to measure for the entire
 675                 // remaining duration of the program.
 676                 if (frame == 10000) {
 677                         frame = 0;
 678                         start = now;
 679                 }
 680 #endif
 681                 check_error();
 682         }
 683
 684         resource_pool->clean_context();
 685 }
 686
 687 void Mixer::get_one_frame_from_each_card(unsigned master_card_index, CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS], bool has_new_frame[MAX_VIDEO_CARDS], int num_samples[MAX_VIDEO_CARDS])
 688 {
 689 start:
 690         // The first card is the master timer, so wait for it to have a new frame.
 691         // TODO: Add a timeout.
 692         unique_lock<mutex> lock(bmusb_mutex);
 693         cards[master_card_index].new_frames_changed.wait(lock, [this, master_card_index]{ return !cards[master_card_index].new_frames.empty() || cards[master_card_index].capture->get_disconnected(); });
 694
 695         if (cards[master_card_index].new_frames.empty()) {
 696                 // We were woken up, but not due to a new frame. Deal with it
 697                 // and then restart.
 698                 assert(cards[master_card_index].capture->get_disconnected());
 699                 handle_hotplugged_cards();
 700                 goto start;
 701         }
 702
 703         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 704                 CaptureCard *card = &cards[card_index];
 705                 if (card->new_frames.empty()) {
 706                         assert(card_index != master_card_index);
 707                         card->queue_length_policy.update_policy(-1);
 708                         continue;
 709                 }
 710                 new_frames[card_index] = move(card->new_frames.front());
 711                 has_new_frame[card_index] = true;
 712                 card->new_frames.pop();
 713                 card->new_frames_changed.notify_all();
 714
 715                 int num_samples_times_timebase = OUTPUT_FREQUENCY * new_frames[card_index].length + card->fractional_samples;
 716                 num_samples[card_index] = num_samples_times_timebase / TIMEBASE;
 717                 card->fractional_samples = num_samples_times_timebase % TIMEBASE;
 718                 assert(num_samples[card_index] >= 0);
 719
 720                 if (card_index == master_card_index) {
 721                         // We don't use the queue length policy for the master card,
 722                         // but we will if it stops being the master. Thus, clear out
 723                         // the policy in case we switch in the future.
 724                         card->queue_length_policy.reset(card_index);
 725                 } else {
 726                         // If we have excess frames compared to the policy for this card,
 727                         // drop frames from the head.
 728                         card->queue_length_policy.update_policy(card->new_frames.size());
 729                         while (card->new_frames.size() > card->queue_length_policy.get_safe_queue_length()) {
 730                                 card->new_frames.pop();
 731                         }
 732                 }
 733         }
 734 }
 735
 736 void Mixer::handle_hotplugged_cards()
 737 {
 738         // Check for cards that have been disconnected since last frame.
 739         for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 740                 CaptureCard *card = &cards[card_index];
 741                 if (card->capture->get_disconnected()) {
 742                         fprintf(stderr, "Card %u went away, replacing with a fake card.\n", card_index);
 743                         FakeCapture *capture = new FakeCapture(WIDTH, HEIGHT, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
 744                         configure_card(card_index, capture, /*is_fake_capture=*/true);
 745                         card->queue_length_policy.reset(card_index);
 746                         card->capture->start_bm_capture();
 747                 }
 748         }
 749
 750         // Check for cards that have been connected since last frame.
 751         vector<libusb_device *> hotplugged_cards_copy;
 752         {
 753                 lock_guard<mutex> lock(hotplug_mutex);
 754                 swap(hotplugged_cards, hotplugged_cards_copy);
 755         }
 756         for (libusb_device *new_dev : hotplugged_cards_copy) {
 757                 // Look for a fake capture card where we can stick this in.
 758                 int free_card_index = -1;
 759                 for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
 760                         if (cards[card_index].is_fake_capture) {
 761                                 free_card_index = int(card_index);
 762                                 break;
 763                         }
 764                 }
 765
 766                 if (free_card_index == -1) {
 767                         fprintf(stderr, "New card plugged in, but no free slots -- ignoring.\n");
 768                         libusb_unref_device(new_dev);
 769                 } else {
 770                         // BMUSBCapture takes ownership.
 771                         fprintf(stderr, "New card plugged in, choosing slot %d.\n", free_card_index);
 772                         CaptureCard *card = &cards[free_card_index];
 773                         BMUSBCapture *capture = new BMUSBCapture(free_card_index, new_dev);
 774                         configure_card(free_card_index, capture, /*is_fake_capture=*/false);
 775                         card->queue_length_policy.reset(free_card_index);
 776                         capture->set_card_disconnected_callback(bind(&Mixer::bm_hotplug_remove, this, free_card_index));
 777                         capture->start_bm_capture();
 778                 }
 779         }
 780 }
 781
 782
 783 void Mixer::schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame)
 784 {
 785         // Resample the audio as needed, including from previously dropped frames.
 786         assert(num_cards > 0);
 787         for (unsigned frame_num = 0; frame_num < dropped_frames + 1; ++frame_num) {
 788                 const bool dropped_frame = (frame_num != dropped_frames);
 789                 {
 790                         // Signal to the audio thread to process this frame.
 791                         // Note that if the frame is a dropped frame, we signal that
 792                         // we don't want to use this frame as base for adjusting
 793                         // the resampler rate. The reason for this is that the timing
 794                         // of these frames is often way too late; they typically don't
 795                         // “arrive” before we synthesize them. Thus, we could end up
 796                         // in a situation where we have inserted e.g. five audio frames
 797                         // into the queue before we then start pulling five of them
 798                         // back out. This makes ResamplingQueue overestimate the delay,
 799                         // causing undue resampler changes. (We _do_ use the last,
 800                         // non-dropped frame; perhaps we should just discard that as well,
 801                         // since dropped frames are expected to be rare, and it might be
 802                         // better to just wait until we have a slightly more normal situation).
 803                         unique_lock<mutex> lock(audio_mutex);
 804                         bool adjust_rate = !dropped_frame;
 805                         audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate});
 806                         audio_task_queue_changed.notify_one();
 807                 }
 808                 if (dropped_frame) {
 809                         // For dropped frames, increase the pts. Note that if the format changed
 810                         // in the meantime, we have no way of detecting that; we just have to
 811                         // assume the frame length is always the same.
 812                         pts_int += length_per_frame;
 813                 }
 814         }
 815 }
 816
 817 void Mixer::render_one_frame(int64_t duration)
 818 {
 819         // Get the main chain from the theme, and set its state immediately.
 820         Theme::Chain theme_main_chain = theme->get_chain(0, pts(), WIDTH, HEIGHT, input_state);
 821         EffectChain *chain = theme_main_chain.chain;
 822         theme_main_chain.setup_chain();
 823         //theme_main_chain.chain->enable_phase_timing(true);
 824
 825         GLuint y_tex, cbcr_tex;
 826         bool got_frame = video_encoder->begin_frame(&y_tex, &cbcr_tex);
 827         assert(got_frame);
 828
 829         // Render main chain.
 830         GLuint cbcr_full_tex = resource_pool->create_2d_texture(GL_RG8, WIDTH, HEIGHT);
 831         GLuint rgba_tex = resource_pool->create_2d_texture(GL_RGB565, WIDTH, HEIGHT);  // Saves texture bandwidth, although dithering gets messed up.
 832         GLuint fbo = resource_pool->create_fbo(y_tex, cbcr_full_tex, rgba_tex);
 833         check_error();
 834         chain->render_to_fbo(fbo, WIDTH, HEIGHT);
 835         resource_pool->release_fbo(fbo);
 836
 837         subsample_chroma(cbcr_full_tex, cbcr_tex);
 838         resource_pool->release_2d_texture(cbcr_full_tex);
 839
 840         // Set the right state for rgba_tex.
 841         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 842         glBindTexture(GL_TEXTURE_2D, rgba_tex);
 843         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 844         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 845         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 846
 847         const int64_t av_delay = TIMEBASE / 10;  // Corresponds to the fixed delay in resampling_queue.h. TODO: Make less hard-coded.
 848         RefCountedGLsync fence = video_encoder->end_frame(pts_int + av_delay, duration, theme_main_chain.input_frames);
 849
 850         // The live frame just shows the RGBA texture we just rendered.
 851         // It owns rgba_tex now.
 852         DisplayFrame live_frame;
 853         live_frame.chain = display_chain.get();
 854         live_frame.setup_chain = [this, rgba_tex]{
 855                 display_input->set_texture_num(rgba_tex);
 856         };
 857         live_frame.ready_fence = fence;
 858         live_frame.input_frames = {};
 859         live_frame.temp_textures = { rgba_tex };
 860         output_channel[OUTPUT_LIVE].output_frame(live_frame);
 861
 862         // Set up preview and any additional channels.
 863         for (int i = 1; i < theme->get_num_channels() + 2; ++i) {
 864                 DisplayFrame display_frame;
 865                 Theme::Chain chain = theme->get_chain(i, pts(), WIDTH, HEIGHT, input_state);  // FIXME: dimensions
 866                 display_frame.chain = chain.chain;
 867                 display_frame.setup_chain = chain.setup_chain;
 868                 display_frame.ready_fence = fence;
 869                 display_frame.input_frames = chain.input_frames;
 870                 display_frame.temp_textures = {};
 871                 output_channel[i].output_frame(display_frame);
 872         }
 873 }
 874
 875 void Mixer::send_audio_level_callback()
 876 {
 877         if (audio_level_callback == nullptr) {
 878                 return;
 879         }
 880
 881         unique_lock<mutex> lock(audio_measure_mutex);
 882         double loudness_s = r128.loudness_S();
 883         double loudness_i = r128.integrated();
 884         double loudness_range_low = r128.range_min();
 885         double loudness_range_high = r128.range_max();
 886
 887         audio_level_callback(loudness_s, to_db(peak),
 888                 loudness_i, loudness_range_low, loudness_range_high,
 889                 audio_mixer.get_gain_staging_db(),
 890                 audio_mixer.get_final_makeup_gain_db(),
 891                 correlation.get_correlation());
 892 }
 893
 894 void Mixer::audio_thread_func()
 895 {
 896         while (!should_quit) {
 897                 AudioTask task;
 898
 899                 {
 900                         unique_lock<mutex> lock(audio_mutex);
 901                         audio_task_queue_changed.wait(lock, [this]{ return should_quit || !audio_task_queue.empty(); });
 902                         if (should_quit) {
 903                                 return;
 904                         }
 905                         task = audio_task_queue.front();
 906                         audio_task_queue.pop();
 907                 }
 908
 909                 ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
 910                         task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
 911                 process_audio_one_frame(task.pts_int, task.num_samples, rate_adjustment_policy);
 912         }
 913 }
 914
 915 void Mixer::process_audio_one_frame(int64_t frame_pts_int, int num_samples, ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy)
 916 {
 917         vector<float> samples_out = audio_mixer.get_output(double(frame_pts_int) / TIMEBASE, num_samples, rate_adjustment_policy);
 918
 919         // Upsample 4x to find interpolated peak.
 920         peak_resampler.inp_data = samples_out.data();
 921         peak_resampler.inp_count = samples_out.size() / 2;
 922
 923         vector<float> interpolated_samples_out;
 924         interpolated_samples_out.resize(samples_out.size());
 925         {
 926                 unique_lock<mutex> lock(audio_measure_mutex);
 927
 928                 while (peak_resampler.inp_count > 0) {  // About four iterations.
 929                         peak_resampler.out_data = &interpolated_samples_out[0];
 930                         peak_resampler.out_count = interpolated_samples_out.size() / 2;
 931                         peak_resampler.process();
 932                         size_t out_stereo_samples = interpolated_samples_out.size() / 2 - peak_resampler.out_count;
 933                         peak = max<float>(peak, find_peak(interpolated_samples_out.data(), out_stereo_samples * 2));
 934                         peak_resampler.out_data = nullptr;
 935                 }
 936         }
 937
 938         // Find R128 levels and L/R correlation.
 939         vector<float> left, right;
 940         deinterleave_samples(samples_out, &left, &right);
 941         float *ptrs[] = { left.data(), right.data() };
 942         {
 943                 unique_lock<mutex> lock(audio_measure_mutex);
 944                 r128.process(left.size(), ptrs);
 945                 audio_mixer.set_current_loudness(r128.loudness_M());
 946                 correlation.process_samples(samples_out);
 947         }
 948
 949         // Send the samples to the sound card.
 950         if (alsa) {
 951                 alsa->write(samples_out);
 952         }
 953
 954         // And finally add them to the output.
 955         video_encoder->add_audio(frame_pts_int, move(samples_out));
 956 }
 957
 958 void Mixer::subsample_chroma(GLuint src_tex, GLuint dst_tex)
 959 {
 960         GLuint vao;
 961         glGenVertexArrays(1, &vao);
 962         check_error();
 963
 964         glBindVertexArray(vao);
 965         check_error();
 966
 967         // Extract Cb/Cr.
 968         GLuint fbo = resource_pool->create_fbo(dst_tex);
 969         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 970         glViewport(0, 0, WIDTH/2, HEIGHT/2);
 971         check_error();
 972
 973         glUseProgram(cbcr_program_num);
 974         check_error();
 975
 976         glActiveTexture(GL_TEXTURE0);
 977         check_error();
 978         glBindTexture(GL_TEXTURE_2D, src_tex);
 979         check_error();
 980         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 981         check_error();
 982         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 983         check_error();
 984         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 985         check_error();
 986
 987         float chroma_offset_0[] = { -0.5f / WIDTH, 0.0f };
 988         set_uniform_vec2(cbcr_program_num, "foo", "chroma_offset_0", chroma_offset_0);
 989
 990         glBindBuffer(GL_ARRAY_BUFFER, cbcr_vbo);
 991         check_error();
 992
 993         for (GLint attr_index : { cbcr_position_attribute_index, cbcr_texcoord_attribute_index }) {
 994                 glEnableVertexAttribArray(attr_index);
 995                 check_error();
 996                 glVertexAttribPointer(attr_index, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
 997                 check_error();
 998         }
 999
1000         glDrawArrays(GL_TRIANGLES, 0, 3);
1001         check_error();
1002
1003         for (GLint attr_index : { cbcr_position_attribute_index, cbcr_texcoord_attribute_index }) {
1004                 glDisableVertexAttribArray(attr_index);
1005                 check_error();
1006         }
1007
1008         glUseProgram(0);
1009         check_error();
1010         glBindFramebuffer(GL_FRAMEBUFFER, 0);
1011         check_error();
1012
1013         resource_pool->release_fbo(fbo);
1014         glDeleteVertexArrays(1, &vao);
1015 }
1016
1017 void Mixer::release_display_frame(DisplayFrame *frame)
1018 {
1019         for (GLuint texnum : frame->temp_textures) {
1020                 resource_pool->release_2d_texture(texnum);
1021         }
1022         frame->temp_textures.clear();
1023         frame->ready_fence.reset();
1024         frame->input_frames.clear();
1025 }
1026
1027 void Mixer::start()
1028 {
1029         mixer_thread = thread(&Mixer::thread_func, this);
1030         audio_thread = thread(&Mixer::audio_thread_func, this);
1031 }
1032
1033 void Mixer::quit()
1034 {
1035         should_quit = true;
1036         audio_task_queue_changed.notify_one();
1037         mixer_thread.join();
1038         audio_thread.join();
1039 }
1040
1041 void Mixer::transition_clicked(int transition_num)
1042 {
1043         theme->transition_clicked(transition_num, pts());
1044 }
1045
1046 void Mixer::channel_clicked(int preview_num)
1047 {
1048         theme->channel_clicked(preview_num);
1049 }
1050
1051 void Mixer::reset_meters()
1052 {
1053         unique_lock<mutex> lock(audio_measure_mutex);
1054         peak_resampler.reset();
1055         peak = 0.0f;
1056         r128.reset();
1057         r128.integr_start();
1058         correlation.reset();
1059 }
1060
1061 void Mixer::start_mode_scanning(unsigned card_index)
1062 {
1063         assert(card_index < num_cards);
1064         if (is_mode_scanning[card_index]) {
1065                 return;
1066         }
1067         is_mode_scanning[card_index] = true;
1068         mode_scanlist[card_index].clear();
1069         for (const auto &mode : cards[card_index].capture->get_available_video_modes()) {
1070                 mode_scanlist[card_index].push_back(mode.first);
1071         }
1072         assert(!mode_scanlist[card_index].empty());
1073         mode_scanlist_index[card_index] = 0;
1074         cards[card_index].capture->set_video_mode(mode_scanlist[card_index][0]);
1075         last_mode_scan_change[card_index] = steady_clock::now();
1076 }
1077
1078 Mixer::OutputChannel::~OutputChannel()
1079 {
1080         if (has_current_frame) {
1081                 parent->release_display_frame(&current_frame);
1082         }
1083         if (has_ready_frame) {
1084                 parent->release_display_frame(&ready_frame);
1085         }
1086 }
1087
1088 void Mixer::OutputChannel::output_frame(DisplayFrame frame)
1089 {
1090         // Store this frame for display. Remove the ready frame if any
1091         // (it was seemingly never used).
1092         {
1093                 unique_lock<mutex> lock(frame_mutex);
1094                 if (has_ready_frame) {
1095                         parent->release_display_frame(&ready_frame);
1096                 }
1097                 ready_frame = frame;
1098                 has_ready_frame = true;
1099         }
1100
1101         if (new_frame_ready_callback) {
1102                 new_frame_ready_callback();
1103         }
1104
1105         // Reduce the number of callbacks by filtering duplicates. The reason
1106         // why we bother doing this is that Qt seemingly can get into a state
1107         // where its builds up an essentially unbounded queue of signals,
1108         // consuming more and more memory, and there's no good way of collapsing
1109         // user-defined signals or limiting the length of the queue.
1110         if (transition_names_updated_callback) {
1111                 vector<string> transition_names = global_mixer->get_transition_names();
1112                 bool changed = false;
1113                 if (transition_names.size() != last_transition_names.size()) {
1114                         changed = true;
1115                 } else {
1116                         for (unsigned i = 0; i < transition_names.size(); ++i) {
1117                                 if (transition_names[i] != last_transition_names[i]) {
1118                                         changed = true;
1119                                         break;
1120                                 }
1121                         }
1122                 }
1123                 if (changed) {
1124                         transition_names_updated_callback(transition_names);
1125                         last_transition_names = transition_names;
1126                 }
1127         }
1128         if (name_updated_callback) {
1129                 string name = global_mixer->get_channel_name(channel);
1130                 if (name != last_name) {
1131                         name_updated_callback(name);
1132                         last_name = name;
1133                 }
1134         }
1135         if (color_updated_callback) {
1136                 string color = global_mixer->get_channel_color(channel);
1137                 if (color != last_color) {
1138                         color_updated_callback(color);
1139                         last_color = color;
1140                 }
1141         }
1142 }
1143
1144 bool Mixer::OutputChannel::get_display_frame(DisplayFrame *frame)
1145 {
1146         unique_lock<mutex> lock(frame_mutex);
1147         if (!has_current_frame && !has_ready_frame) {
1148                 return false;
1149         }
1150
1151         if (has_current_frame && has_ready_frame) {
1152                 // We have a new ready frame. Toss the current one.
1153                 parent->release_display_frame(&current_frame);
1154                 has_current_frame = false;
1155         }
1156         if (has_ready_frame) {
1157                 assert(!has_current_frame);
1158                 current_frame = ready_frame;
1159                 ready_frame.ready_fence.reset();  // Drop the refcount.
1160                 ready_frame.input_frames.clear();  // Drop the refcounts.
1161                 has_current_frame = true;
1162                 has_ready_frame = false;
1163         }
1164
1165         *frame = current_frame;
1166         return true;
1167 }
1168
1169 void Mixer::OutputChannel::set_frame_ready_callback(Mixer::new_frame_ready_callback_t callback)
1170 {
1171         new_frame_ready_callback = callback;
1172 }
1173
1174 void Mixer::OutputChannel::set_transition_names_updated_callback(Mixer::transition_names_updated_callback_t callback)
1175 {
1176         transition_names_updated_callback = callback;
1177 }
1178
1179 void Mixer::OutputChannel::set_name_updated_callback(Mixer::name_updated_callback_t callback)
1180 {
1181         name_updated_callback = callback;
1182 }
1183
1184 void Mixer::OutputChannel::set_color_updated_callback(Mixer::color_updated_callback_t callback)
1185 {
1186         color_updated_callback = callback;
1187 }
1188
1189 mutex RefCountedGLsync::fence_lock;